Yakima River Spring Chinook Enhancement Study, 1987 Annual Report.
The smelt outmigration was monitored at wapatox on the Naches River and Prosser on the lower Yakima. The spring outmigration at Wapatox was estimated to be 16,141 smolts. The 1987 spring outmigration of wild spring chinook from the Yakima Basin was estimated to be 251,975 smolts at Prosser. The survival from egg to smelt was calculated using the 1985 redd counts and the 1987 smolt outmigration at Prosser. The estimated survival was 4.16%, which gives a mean egg to smolt survival over four years of 6.32%. In 1987 a total of 3,683 adult and 335 jack spring chinook salmon returning to the Yakima River were counted at Prosser fish ladder. This gives a total of 4,018 salmon returning to Prosser Dam. The median dates of passage were May 12 and May 16 for adults and jacks respectively. An additional 372 fish were estimated to have been caught in the Yakima River subsistence dipnet fishery below Horn Rapids and Prosser Dams. Therefore, total return to the Yakima system was 4,390 spring chinook salmon. Spring chinook were counted at Roza Dam from May 1 to September 30, 1987. Passage at Roza Dam was 1,610 adult and 67 jack spring chinook for a total of 1,677 wild fish. The median dates of passage at Roza Dam were May 29 and May 26 for spring chinook adults and jacks respectively. The smolt to adult (S{sub sa}) survival was calculated based on the 1983 smelt outmigration estimated at Prosser and the 1984 return of jacks (3 year old fish) the 1985 return of four year old adults, and the 1986 return of five year old fish to the Yakima River. It was estimated that 6,012 wild three, four, and five year old fish returned from an estimated smolt outmigration of 135,548 fish in 1983. This gives an estimated survival from smolt to adult of 4.4%. The smolt to adult survival for the 1984 smolt outmigration was 5.3% with 423 jacks returning in 1985, 5,163 four year old adults returning in 1986, and 983 five year old fish returning in 1987 fran an estimated 123,732 smolts in 1984. Spring chinook adults from fourteen different hatchery release groups were recovered in 1987. A total of 211 coded wire tags were recovered and these were expanded to an estimated 253 returning hatchery fish in 1987. Nine of these fish were jacks.
- Research Organization:
- Yakima Indian Nation
- Sponsoring Organization:
- United States. Bonneville Power Administration.
- DOE Contract Number:
- 1983BP39461
- OSTI ID:
- 915095
- Report Number(s):
- DOE/BP-39461-4; R&D Project: 1982-016-00; TRN: US200817%%245
- Country of Publication:
- United States
- Language:
- English
Similar Records
Yakima River Spring Chinook Enhancement Study, 1988 Annual Report.
Yakima River Spring Chinook Enhancement Study, 1989 Annual Report.